Jano:
This is what I have been told about barrel break in. Is the following information true? I don't know. It sounds plausible to me. Can you get away with not doing a barrel break in? Probably. Maybe the only people who would notice a difference are benchrest target shooters.
I was told by a benchrest target shooter that a new barrel has imperfections from machining -- tool marks that can be considered to be jagged edges on the otherwise smooth surface of the barrel -- the lands of the barrel to be precise. When you shoot copper jacketed bullets through such a barrel having jagged edges excessive copper fouling -- deposition of copper material on the rifling lands, on the barrel surface -- which leads to shooting inaccuracy. My shooting bullets through the barrel, these jagged edges are worn down and smoothed out. However, this smoothing out process is reduced when copper is already rubbed off on these jagged edges. So, when a barrel is brand new, shoot one shot, clean out the copper, shoot another shot, clean out the copper, shoot a third shot, clean out the copper. Next, shoot three shots, clean out the copper, shoot another three shots, clean out the coppper, shoot another three shots, clean out the copper. Then, shoot groups of five shots, clean out the copper, and repeat until you have shot 100 or 150 rounds. After this process the jagged edges should be smoothed down reasonably well. If you fail to clean the copper early on, you can always clean it out later, you just are delaying the smoothing process. One effect he mentioned is that carbon can be deposited in the barrel in association with these jagged edges if you don't follow this process, and that the carbon WILL NOT otherwise come out with further cleaning once it is deposited.
Is this necessary? Is this guy's explanation correct? I have no idea. I do it with my new barrels because it seems the safe thing to do. Will it ever make a difference in my shooting -- I'm NOT a super accurate benchrest shooter but a hunter looking for good in-the-field hunting accuracy -- I don't know.
On the separate subject of firing rounds and letting the barrel cool off, the issue is that shooting rounds through a "hot" barrel can cause pre-mature erosion of the barrel at the throat -- where the bullet first enters the barrel -- and reduce the accuracy of the rifle. Does this mean that a barrel that otherwise would be good for 30,000 rounds will only last 15,000 rounds or that a barrel good for 5,000 rounds will only last 1,000 rounds? I don't know. I wait 60 seconds between all the rounds I fire, and if the barrel is too hot for me to hold my hand on it comfortably, I will wait longer. Is this necessary? I don't know. I doubt I'm harming my rifle by waiting this long between firing rounds -- by firing faster maybe I WOULD damage my rifle barrel. I'm being safe. What should one do? That is up to you.
